Valve Mounting Structure for a Loader Work Vehicle, and a Loader Work Vehicle

ABSTRACT

A front loader  3  is connected to a front portion of a tractor  1  having a tractor body. The front loader  3  includes mounting frames  7  arranged at right and left sides of the tractor body, booms  8  pivotally supported by upper ends of the mounting frames  7  to be vertically swingable, and a working implement  9  swingably connected to distal ends of the booms  8 . A control valve  45  is disposed outside the tractor body  2  and rearwardly of one of the mounting frames  7  for controlling hydraulic cylinders  17, 29.

TECHNICAL FIELD

This invention relates to a valve mounting structure for a loader workvehicle having a front loader attached to the front of a tractor, and tothe loader work vehicle.

BACKGROUND ART

A loader work vehicle has a front loader attached to the front of atractor. The front loader has mounting frames provided at right and leftsides of a tractor body, booms vertically swingably connected to upperportions of the mounting frames, a working implement such as a bucketswingably connected to distal ends of the booms, boom cylinders forswinging the booms, and an implement cylinder for swinging the workingimplement. Each of the right and left mounting frames has a support baseprotrude laterally outward of the tractor body, a main frame attached toa laterally outward end of the support base to project upward, and aside frame detachably attached to the main frame to project upward. Eachboom has a proximal end thereof vertically swingably attached to anupper end of the side frame.

The conventional loader working vehicle of this type includes a controlvalve disposed outside or in an upper position of the main frames of themounting frame for controlling the hydraulic cylinders of the frontloader (JP2001-140276A, JP10-280473A, JP10-280464A and JP7-207701A).

DISCLOSURE OF THE INVENTION Problem to be Solved by the Invention

Conventionally, there has been a possibility of the control valveobstructing the field of view, or certain obstacles interfering with thecontrol valve in time of operation.

Having regard to the above drawback, this invention intends to providean improvement to eliminate the possibility of the control valveobstructing the field of view, or certain obstacles interfering with thecontrol valve in time of operation.

Means for Solving the Problem

In a structure for attaching a control valve to a loader work vehicle,according to this invention, a front loader is connected to a frontportion of a tractor having a tractor body,

the front loader including mounting frames arranged at right and leftsides of the tractor body, booms pivotally supported by upper ends ofthe mounting frames to be vertically swingable, and a working implementswingably connected to distal ends of the booms, the control valve beingdisposed outside the tractor body and rearwardly of one of the mountingframes for controlling hydraulic cylinders.

According to the above construction, the control valve is effectivelyprotected by being sandwiched fore and aft between the rigid mountingframe and fuel tank. The control valve is reliably guarded againstinterference from obstacles and the like. Since the control valve isdisposed laterally of the tractor body, there is no possibility of thecontrol valve obstructing the field of view in time of operation.Further, with the control valve disposed rearwardly of the mountingframe, the mounting frame may be used also as a guard for valve hoses.

In the above construction, it is preferred that a valve stay is disposedrearwardly of the one of the mounting frames and projecting laterallyoutward, and the control valve is attached to the valve stay.

It is also preferred that a valve cover is provided for covering atleast areas laterally outward of and below the control valve, andcontrol wires are provided in a plurality corresponding to the spools ofthe control valve, the plurality of control wires being arranged atvertical intervals laterally outward of the fuel tank to extend in thefore and aft direction, and arranged laterally inward of a side wall ofthe valve cover, and passed fore and aft through and held by a laterallyoutward portion of the valve stay.

In the above construction, it is preferred that each of the right andleft mounting frames includes a support base projecting laterallyoutward from the tractor body, a main frame attached to a laterallyoutward end of the support base to project upward, and a side framedetachably attached to the main frame to project upward, one of thebooms being pivotally supported at a proximal end thereof by an upperend of the side frame to be vertically swingable; and

a laterally inward end of the support base is fixed to a connectingframe connected to a front axle frame of the tractor body, the supportbase projecting laterally outward from the connecting frame, the valvestay projecting laterally outward from a position of the connectingframe rearward of the support base, the control valve being disposedrearwardly of the support base and a lower portion of the main frame.

Preferably, the control valve has a plurality of spools corresponding tothe hydraulic cylinders of the front loader; the plurality of spoolsbeing arranged vertically and projecting laterally outward frompositions vertically spaced apart of a valve body, the control valvebeing attached to the valve stay such that a direction of thickness ofthe control valve coincides with a fore and aft direction.

A loader work vehicle according to this invention comprises:

a tractor having a tractor body; and

a front loader connected to a front portion of the tractor;

the front loader including mounting frames arranged at right and leftsides of the tractor body, booms pivotally supported by upper ends ofthe mounting frames to be vertically swingable, and a working implementswingably connected to distal ends of the booms;

wherein a tank is disposed outside the tractor body and rearwardly ofone of the mounting frames, and a control valve is disposed outside thetractor body and rearwardly of the one of the mounting frames forcontrolling hydraulic cylinders of the front loader.

According to this invention, the control valve is effectively protectedby being sandwiched fore and aft between the rigid mounting frame andfuel tank. The control valve is reliably guarded against interferencefrom obstacles and the like. Since the control valve is disposedlaterally of the tractor body, there is no possibility of the controlvalve obstructing the field of view in time of operation. Further, withthe control valve disposed rearwardly of the mounting frame, themounting frame may be used also as a guard for valve hoses.

In the above construction, it is preferred that a valve stay is disposedbetween the tank and the one of the mounting frames and projectinglaterally outward, the control valve being attached to the valve stay.

The above construction may further comprise control wires for operatingthe control valve, the control wires being passed in a fore and aftdirection through and held by the valve stay, and connected to spools ofthe control valve.

The above construction may further comprise a valve cover for coveringat least areas laterally outward of and below the control valve, thecontrol wires being provided in a plurality corresponding to the spoolsof the control valve, the plurality of control wires being arranged atvertical intervals laterally outward of the fuel tank to extend in thefore and aft direction, and arranged laterally inward of a side wall ofthe valve cover, and passed fore and aft through and held by a laterallyoutward portion of the valve stay.

It is preferred that, in the above construction, the tractor body hasconnecting frames connected to a front axle frame; each of the right andleft mounting frames includes a support base projecting laterallyoutward from the tractor body, a main frame attached to a laterallyoutward end of the support base to project upward, and a side framedetachably attached to the main frame to project upward, one of thebooms being pivotally supported at a proximal end thereof by an upperend of the side frame to be vertically swingable; and a laterally inwardend of the support base is fixed to one of the connecting frames, thesupport base projecting laterally outward from the connecting frame, thevalve stay projecting laterally outward from a position of theconnecting frame rearward of the support base, the control valve beingdisposed rearwardly of the support base and a lower portion of the mainframe.

It is also preferred that the control valve has a plurality of spoolscorresponding to the hydraulic cylinders of the front loader; and thecontrol valve is disposed in vertical posture to have the plurality ofspools arranged vertically and projecting laterally outward frompositions vertically spaced apart of a valve body, the control valvebeing attached to the valve stay such that a direction of thickness ofthe control valve coincides with a fore and aft direction.

BEST MODE FOR CARRYING OUT THE INVENTION

An embodiment of this invention will be described hereinafter withreference to the drawings.

FIGS. 1 through 3 show a tractor mounted loader embodying thisinvention. In FIGS. 1 through 3, a tractor 1 has a front loader 3attached to the front thereof.

The tractor 1 has a tractor body 2, a pair of right and left frontwheels 4 and a pair of right and left rear wheels 5, A hood 6 isdisposed on a forward portion for covering an engine, a radiator and soon.

The front loader 3 includes, as main components thereof, a pair of rightand left mounting frames 7, a pair of right and left booms 8, and aworking implement 9 such as a bucket.

Each of the right and left mounting frames 7 includes a cylindricalsupport base 10 projecting laterally outward from the tractor body 2, amain frame 11 attached to a laterally outward end of the support base 10to project upward, and a side frame 12 detachably attached to the mainframe 11 to project upward. These components are arranged at right andleft sides of the tractor body 2. The booms 8 are pivotally supported atproximal ends thereof by upper ends of the side frames 12 to bevertically swingable relative thereto.

The tractor body 2 has connecting frames 2C connected to front axleframe 2A. The connecting frames 2C connect the front axle frame 2A and aflywheel housing, not shown, in the fore and aft direction.

The connecting frames 2C are arranged right and left, each in the formof a plate. Each connecting frame 2C has a front half fixed to a sidesurface of a rear half portion of the front axle frame 2A by a pluralityof bolts, and a rear half fixed to a side surface of the flywheelhousing by a plurality of bolts. The engine (not shown) is connected tothe front of the flywheel housing, and a clutch housing, a transmissioncase 13 and a rear wheel differential are connected in series rearwardlyof the flywheel housing.

The cylindrical support bases 10 are formed of metal pipes such ascylindrical steel pipes. The support bases 10 have inward ends thereof,transversely of the tractor body 2, inserted into circular bores formedin rearward regions of the connecting frames 2C, and fixed welded aroundthe circular bores. Thus, the laterally outward ends of the supportbases 10 project laterally outward of the tractor body 2. The mainframes 11 are attached to the laterally outward ends of the supportbases 10 to project upward. For this purpose, circular bores are formedin lower end regions of the main frames 11, and the laterally outwardends of the support bases 10 are inserted into the circular bores andfixed welded around these bores.

Each main frame 11 has a cylindrical boss 15 formed integral with anupper end portion thereof and having a pin hole extending sideways, anda receiver 16 formed integral with a front portion of a verticallyintermediate region and having an arcuate receiving recess openingupward. Each main frame 11 is in the form of a single plate (thickboard) of steel casting, and has a plurality of reinforcing ribs formedto extend vertically and fore and aft to form a crisscross pattern onboth plate surfaces (or one plate surface). Recesses are formed betweenthe reinforcing ribs to reduce weight.

The above main frames 11 are attached to opposite sides of the tractor 1through the support bases 10 and connecting frames 2C in order toconnect the side frames 12 of the front loader 3 to the front of thetractor 1 to be detachable therefrom.

The side frames 12 are disposed at the rear ends of booms 8 of frontloader 3 in order to connect the front loader 3 to the front of thetractor 1 to be detachable therefrom, by using the main frames 11.

For this purpose, each side frame 12 includes an engaging pin 18 fixedto the lower end thereof for engaging the receiver 16 of thecorresponding main frame 11. Further, each side frame 12 includes acylindrical boss 19 formed integral with a rear portion of a verticallyintermediate region thereof and having a pin bore corresponding to theboss 15 of the main frame 11.

The front loader 3 can be connected to the tractor 1 by engaging theengaging pins 18 of the side frames 12 with the receivers 16 of the mainframes 11, then aligning the bosses 15 and 19, and inserting linkingpins 21 therethrough. The front loader 3 can is separable from thetractor 1 by removing the linking pins 21.

The booms 8 are bent in a longitudinally middle position thereof to forman arched, angular shape, and have a vertical width gradually enlargingfrom the front and rear ends to the longitudinally middle position. Eachboom 8 is wholly formed of a metal plate such as steel plate to have ashape of substantially square pipe. The booms 8 are arranged to form aright and left pair at opposite sides of the hood 6. The pair of booms 8are interconnected in front regions thereof by a connecting pipe 23.

The booms 8 are pivotally connected at proximal ends (rear ends) thereofto the upper ends of the side frames 12 by pins 22 to be verticallyswingable about a transverse axis.

A boom cylinder 17 consisting of a double acting hydraulic cylinderextends between a longitudinally intermediate position of each boom 8and a vertically intermediate position of each side frame 12. The booms8 are swingable by extension and contraction of the right and left boomcylinders 17.

The distal ends (forward ends) of the booms 1 are pivotally connected bypins 24 to lower positions on the back of the working implement 9.Opposite ends of a two-piece flexion link 25 are connected by pins 26and 27 to the back of the working implement 9 and a position adjacentthe forward end of each boom 8. An implement cylinder (bucket cylinder)29 consisting of a double acting hydraulic cylinder extends between anupper surface in a longitudinally intermediate position of each boom 8and an intermediate connection point of the two-piece flexion link 25.The working implement 9 is swingable (for scooping and dumping action)by extension and contraction of the implement cylinder 29.

A stand 33 is attached to lower surfaces of forward regions of the booms8. This stand 33 is used for supporting and self-sustaining the booms 8with the working implement 9 resting on the ground when the front loader3 is separated from the tractor 1. When the front loader 3 is connectedto the tractor 1, the stand 33 may be contained in a position along thelower surface of the forward regions of the booms 8.

The tractor body 2 has rear wheel fenders 35 arranged at opposite sidesof a rear portion thereof for covering inner sides of the rear wheels 5,respectively. A driver's seat 36 is disposed between the right and leftrear wheel fenders 35. A driving section 39 including a steering wheel37 is provided forwardly of the driver's seat 36. A four-strut typerollover protection structure 40 is erected on the tractor body 2 tosurround the driver's seat 36 and driving section 39.

As shown also in FIGS. 4 through 6, a fuel tank 43 is disposed outsidethe tractor body 2 and rearwardly of one of the mounting frames(right-hand frame) 7. A control valve 45 is disposed outside the tractorbody 2 and between this mounting frame 7 and fuel tank 43 forcontrolling the hydraulic cylinders (boom cylinders 17 and implementcylinders 29) of the front loader 3.

In FIGS. 4 through 6, a valve stay 51 projects laterally outward frombetween the fuel tank 43 outside the tractor body 2 and the mountingframe 7. The valve stay 51 is formed of a plate. The valve stay 51 has alaterally inward portion thereof fixed by a fixing device 53 such asbolts and nuts to a mounting piece 52 projecting from the connectingframe 2C. Thus, the valve stay 51 projects from the connecting frame 2Cto separate the fuel tank 43 and mounting frames 7 from each other inthe fore and aft direction. The control valve 45 is attached by afastening device such as bolts and nuts to the front surface of thevalve stay 51. Thus, the valve stay 51 projects laterally outward from aposition rearward of the support base 10 of the connecting frame 2C, andthe control valve 45 is disposed rearwardly of the support base 10 and alower portion of the main frame 11.

The control valve 45 has a plurality of (three in the illustratedexample) spools 57 corresponding to the hydraulic cylinders (boomcylinders 17, implement cylinders 29 and so on) of the front loader 3.The control valve 45 is connected to the boom cylinders 17, implementcylinders 29 and so on through valve hoses 46. By push/pull operation ofthe spools 57, pressure oil may be supplied selectively orsimultaneously to the boom cylinders 17 and implement cylinders 29. Thecontrol valve 45 has the plurality of spools 57 arranged vertically andprojecting laterally outward from positions vertically spaced apart of avalve body. The control valve 45 is attached to the valve stay 51 suchthat the direction of thickness of the control valve 45 coincides withthe fore and aft direction. The control valve 45 has larger vertical andsideways dimensions than a fore and aft dimension.

In this embodiment, the control valve 45 has three spools 57. One of thethree spools 57 serves to feed pressure oil to the boom cylinders 17.Another serves to feed pressure oil to the implement cylinders 29. Theremaining one is used when, for example, a different working implementis provided instead of or in addition to the working implement (bucket)9, and serves to feed pressure oil to a spare or auxiliary hydrauliccylinder, not shown, for actuating the different working implement.

A valve cover 59 is disposed laterally outward of the tractor body 2 forcovering at least areas laterally outward of and below the control valve45. This valve cover 59 has a front wall 61 for closing the front of thecontrol valve 45, a side wall 62 for closing an outer lateral side ofthe control valve 45, and a bottom wall 63 for closing a lower part ofthe control valve 45. Thus, the valve cover 59 is in the form of arectangular box opening upward rearward and laterally inward. The valvecover 59 is fixed by a fixing device 60 such as bolts and nuts to amounting piece 58 projecting forward from an outward end of the valvestay 51. Thus, the valve cover 59 is attached to an outer lateralposition of the tractor body 2 through the valve stay 51.

The side wall 62 and front wall 61 of the valve cover 59 are formed bybending a piece of sheet metal at a right angle. A front slope portion65 inclined rearward and downward is formed at the lower end of thefront wall 61. An outer side slope portion 66 inclined inward anddownward is formed at the lower end of the side wall 62. The bottom wall63 is formed of a piece of sheet metal separate from the front wall 61and side wall 62, and is fixed such as by welding to the front slopeportion 65 of the front wall 6 and the outer side slope portion 66 ofthe side wall 62. The front wall 61 has an upper lid piece 68 and amounting piece 69 formed integral with and bent rearward from the upperend thereof.

The control valve 45 is operable by a plurality of (three) control wires71 corresponding in number to the spools 57 of the control valve 45. Thecontrol wires 71 are arranged at vertical intervals laterally outward ofthe fuel tank 43 to extend in the fore and aft direction, arrangedlaterally inward of the side wall of the valve cover 59, and passed foreand aft through and held by a laterally outward portion of the valvestay 51. Forward ends of the control wires 71 are connected throughlinks 72 to the spools 57 of the control valve 45.

Each control wire 71 is formed of a push-pull cable or Bowden cablehaving an inner wire 73 and an outer wire 75. The outer wire 75 of eachcontrol wire 71 is passed fore and aft through the laterally outwardportion of the valve stay 51 and fixed to the valve stay 51 with nuts77. The inner wire 73 extends through the outer wire 74 past the valvestay 51, 50 that the forward end of the inner wire 73 is connected tothe spool 57 of the control valve 45 through the link 72. Each link 72corresponding to each control wire 71 is supported by a link stay 78 tobe pivotable about a vertical axis. By pulling the inner wire 73 of eachcontrol wire 71, the spool 57 is pulled to open the control valve 45.The spool 57 is pushed back by a spring force. The inner wires 73 of thecontrol wires 71 are pushed and pulled selectively or simultaneously byoperating control levers, not shown, arranged adjacent the driver's seat36,

According to the above embodiment, the fuel tank 43 is disposed outsidethe tractor body 2 and rearwardly of one of the mounting frames 7. Thecontrol valve 45 is disposed outside the tractor body 2 and between oneof the mounting frames 7 and the fuel tank 43 for controlling thehydraulic cylinders 17 and 29 of the front loader 3. Thus, the controlvalve 45 is effectively protected by being sandwiched fore and aftbetween the rigid mounting frame 7 and fuel tank 43. The control valve45 is reliably guarded against interference from obstacles and the like.Since the control valve 45 is disposed laterally of the tractor body 2,there is no possibility of the control valve 45 obstructing the field ofview in time of operation. Further, with the control valve 45 disposedrearwardly of the mounting frame 7 (main frame 11), the mounting frame 7(main frame 11) may be used also as a guard for the valve hoses 46.

The valve stay 51 projects laterally outward from between the fuel tank43 outside the tractor body 2 and the mounting frame 7. The controlvalve 45 is attached to the valve stay 51. The control wires 71 foroperating the control valve 45 are passed in the fore and aft directionthrough and held by the valve stay 51 and connected to the spools 57 ofthe control valve 45. Thus, the control wires 71 for operating thecontrol valve 45 can be fixed by using the valve stay 51 for attachingthe control valve 45, This allows the control wires 71 to be arranged inproper positions corresponding to the spools 57, and can secure spacefor arranging and fixing the control wires 71.

The valve cover 59 is provided to cover at least areas laterally outwardof and below the control valve 45. A plurality of control wires 71 areprovided to correspond in number to the spools 57 of the control valve45, The control wires 71 are arranged at vertical intervals laterallyoutward of the fuel tank 43 to extend in the fore and aft direction, andarranged laterally inward of the side wall of the valve cover 59, andpassed fore and aft through and held by a laterally outward portion ofthe valve stay 51. Thus, the side wall of the valve cover 59 caneffectively protect the plurality of control wires 71, and the controlwires 71 can be arranged tidily.

Further, the control valve 45 has a plurality of spools 57 correspondingto the hydraulic cylinders 17 and 29 of the front loader 3. The controlvalve 45 is disposed in vertical posture to have the plurality of spools57 arranged at vertical intervals and projecting laterally outward fromthe valve body. The control valve 45 is attached to the valve stay 51,to have the direction of thickness thereof coinciding with the fore andaft direction. By setting the control valve 45 to the vertical posture,the control valve 45 may be placed compactly between the fuel tank 43and mounting frame 7 (main frame 11). In this way, effective use is madeof the space laterally of the tractor body 2 between the fuel tank 43and mounting frame 7.

In the above embodiment, the fuel tank 43 is disposed at the right sideof the tractor body 2 and rearwardly of the right mounting frame 7. Thecontrol valve 45 is disposed at the right side of the tractor body 2 andbetween the right mounting frames 7 and the fuel tank 43. Instead, theoil tank and other tanks may be arranged rearwardly of the mountingframe 7, and the control valve 45 may disposed between the mountingframe 7, and the oil tank and other tanks. The fuel tank 43 may bedisposed at the left side of the tractor body 2 and rearwardly of theleft mounting frames 7, and the control valve 45 disposed at the leftside of the tractor body 2 and between the left mounting frame 7 and thefuel tank 43.

In the above embodiment, the control valve 45 has three spools 57corresponding to the hydraulic cylinders 17 and 29 of the front loader3, and three control wires 71 for operating the control valve 45 areprovided to correspond to the spools 57, The number of spools andcontrol wires is not limited to this. The number of spools 57 andcontrol wires 71 may be one or two each, or four or more, of course.

In the above embodiment, the valve cover 59 has a front wall 61 forclosing the front of the control valve 45, a side wall 62 for closing anouter lateral side of the control valve 45, and a bottom wall 63 forclosing a lower part of the control valve 45. Since the front and backof the control valve 45 can be protected by the tank 43 and mountingframe 7, the valve cover 59 may cover only the outer lateral side andlower part of the control valve 45. Thus, the valve cover 59 may havethe side wall 62 and bottom wall 63, with the front wall 61 omitted. Thefront wall 61 may have a cutout in a portion thereof opposed to the mainframe 11.

This invention is applicable to a loader work vehicle with a frontloader attached to a tractor.

BRIEF DESCRIPTION OF THE DRAWINGS

[FIG. 1] Side view of a tractor-mounted loader in one embodiment of thisinvention

[FIG. 2] Plan view of the tractor-mounted loader

[FIG. 3] Front view of the tractor-mounted loader

[FIG. 4] Side view of a control valve mounting portion

[FIG. 5] Plan view of the control valve mounting portion

[FIG. 6] Front view of the control valve mounting portion

DESCRIPTION OF THE REFERENCES

-   -   1 tractor    -   2 tractor body    -   3 front loader    -   7 mounting frames    -   8 booms    -   9 working implement (bucket)    -   10 support bases    -   11 main frames    -   12 side frames    -   17 boom cylinders    -   29 implement cylinders    -   43 fuel tank    -   45 control valve    -   51 valve stay    -   57 spools    -   59 valve cover    -   62 side wall    -   71 control wires    -   72 links

1. A structure for attaching a control valve to a loader work vehiclewith a front loader connected to a front portion of a tractor having atractor body, said front loader including mounting frames arranged atright and left sides of said tractor body, booms pivotally supported byupper ends of the mounting frames to be vertically swingable, and aworking implement swingably connected to distal ends of the booms, saidcontrol valve being disposed outside said tractor body and rearwardly ofone of said mounting frames for controlling hydraulic cylinders.
 2. Astructure for attaching a control valve as defined in claim 1,comprising a valve stay disposed rearwardly of said one of said mountingframes and projecting laterally outward, said control valve beingattached to said valve stay.
 3. A structure for attaching a controlvalve as defined in claim 2, wherein control wires for operating saidcontrol valve are passed in a fore and aft direction through and held bysaid valve stay, said control wires being connected to spools of saidcontrol valve.
 4. A structure for attaching a control valve as definedin claim 3, wherein a valve cover is provided for covering at leastareas laterally outward of and below the control valve, said controlwires being provided in a plurality corresponding to the spools of thecontrol valve, the plurality of control wires being arranged at verticalintervals laterally outward of the fuel tank to extend in the fore andaft direction, and arranged laterally inward of a side wall of the valvecover, and passed fore and aft through and held by a laterally outwardportion of the valve stay.
 5. A structure for attaching a control valveas defined in claim 2, wherein: each of the right and left mountingframes includes a support base projecting laterally outward from thetractor body, a main frame attached to a laterally outward end of thesupport base to project upward, and a side frame detachably attached tothe main frame to project upward, one of the booms being pivotallysupported at a proximal end thereof by an upper end of the side frame tobe vertically swingable; and a laterally inward end of said support baseis fixed to a connecting frame connected to a front axle frame of saidtractor body, said support base projecting laterally outward from theconnecting frame, said valve stay projecting laterally outward from aposition of the connecting frame rearward of the support base, saidcontrol valve being disposed rearwardly of the support base and a lowerportion of the main frame.
 6. A structure for attaching a control valveas defined in claim 1, wherein: said control valve has a plurality ofspools corresponding to the hydraulic cylinders of the front loader; theplurality of spools being arranged vertically and projecting laterallyoutward from positions vertically spaced apart of a valve body, saidcontrol valve being attached to the valve stay such that a direction ofthickness of the control valve coincides with a fore and aft direction.7. A loader work vehicle comprising: a tractor having a tractor body;and a front loader connected to a front portion of the tractor; saidfront loader including mounting frames arranged at right and left sidesof said tractor body, booms pivotally supported by upper ends of themounting frames to be vertically swingable, and a working implementswingably connected to distal ends of the booms; wherein a tank isdisposed outside the tractor body and rearwardly of one of the mountingframes, and a control valve is disposed outside said tractor body andrearwardly of said one of said mounting frames for controlling hydrauliccylinders of the front loader.
 8. A loader work vehicle as defined inclaim 7, further comprising a valve stay disposed between said tank andsaid one of said mounting frames and projecting laterally outward, saidcontrol valve being attached to said valve stay.
 9. A loader workvehicle as defined in claim 8, further comprising control wires foroperating said control valve, said control wires being passed in a foreand aft direction through and held by said valve stay, and connected tospools of said control valve.
 10. A loader work vehicle as defined inclaim 9, further comprising a valve cover for covering at least areaslaterally outward of and below the control valve, said control wiresbeing provided in a plurality corresponding to the spools of the controlvalve, the plurality of control wires being arranged at verticalintervals laterally outward of the fuel tank to extend in the fore andaft direction, and arranged laterally inward of a side wall of the valvecover, and passed fore and aft through and held by a laterally outwardportion of the valve stay.
 11. A loader work vehicle as defined in claim8, wherein: said tractor body has connecting frames connected to a frontaxle frame; each of the right and left mounting frames includes asupport base projecting laterally outward from the tractor body, a mainframe attached to a laterally outward end of the support base to projectupward, and a side frame detachably attached to the main frame toproject upward, one of the booms being pivotally supported at a proximalend thereof by an upper end of the side frame to be verticallyswingable; and a laterally inward end of said support base is fixed toone of said connecting frames, said support base projecting laterallyoutward from the connecting frame, said valve stay projecting laterallyoutward from a position of the connecting frame rearward of the supportbase, said control valve being disposed rearwardly of the support baseand a lower portion of the main frame.
 12. A loader work vehicle asdefined in claim 8, wherein said control valve has a plurality of spoolscorresponding to the hydraulic cylinders of the front loader; and saidcontrol valve is disposed in vertical posture to have the plurality ofspools arranged vertically and projecting laterally outward frompositions vertically spaced apart of a valve body, said control valvebeing attached to the valve stay such that a direction of thickness ofthe control valve coincides with a fore and aft direction.